Abstract
AbstractThe synthesis and characterization of two diethylenetriaminepentaacetic acid (DTPA) based heteropolymetallic metallostar lanthanide complexes with the general formulas (GdL1)3Ln and (GdL2)3Ln are described. The synthesis uses a synthetic approach recently developed in our group for the selective complexation of gadolinium(III) and luminescent lanthanide ions with a ditopic ligand to form highly paramagnetic and luminescent metallostar complexes. The luminescence data and relaxometric studies suggest the potential applicability of the complexes as bimodal contrast agents for magnetic resonance and optical imaging. Owing to the higher excited state of L1, better sensitization was observed for all (GdL1)3Ln complexes than for (GdL2)3Ln. A large increase of the quantum yield from 1.5 to 9.8 % was observed for the (GdL1)3Eu complex compared with (GdL2)3Eu, whereas the (GdL1)3Tb complex exhibited a quantum yield (QY) of 30.9 % compared with 15.3 % for (GdL2)3Tb. A slight increase of the QY from 0.8 to 1.2 % was observed for the Dy(III) complex when switching from ligand L2 to L1. The nuclear magnetic relaxation dispersion (NMRD) measurements of the (GdL2)3Ln complexes (Ln = EuIII, DyIII, TbIII) showed respective longitudinal relaxivity (r1) values of 24.27, 22.80 and 21.72 s–1 mmol–1 per metallostar complex at 310 K and 20 MHz.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.